George Manuel Flores, head of the Varrio Hawaiian Gardens street gang, had pleaded guilty to racketeering conspiracy in a case involving drug sales.

A reputed drug kingpin and key defendant in a federal gang sweep was sentenced Monday to 30 years in federal prison for overseeing the racketeering and drug activities of the Varrio Hawaiian Gardens street gang.

George Manuel Flores, also known as "Boxer," 43, was arrested in 2009 as part of Operation Knockout, one of the nation's largest gang sweeps and the culmination of an investigation that began after the fatal shooting of Los Angeles Sheriff's Deputy Jerry Ortiz in 2005.

Flores was identified as a leader of the Hawaiian Gardens gang who issued orders to other Varrio members and directed the collection of "taxes" from drug dealers in the tiny city in southeastern L.A. County.

Flores, who pleaded guilty last March to racketeering conspiracy, being a felon in possession of ammunition and various drug charges, was sentenced Monday by U.S. District Judge Dale S. Fischer. In court documents, prosecutors portrayed Flores as a drug lord.

"For over a decade, [Flores] ran what are fairly described as several illegal drug 'supermarkets' from houses in Hawaiian Gardens that were open 24 hours a day, seven days a week, at which his customers could buy the drug of their choice," prosecutor Michael Lowe wrote.

U.S. Atty. André Birotte Jr. said Flores "tormented the city of Hawaiian Gardens for decades."

As part of the plea, Flores admitted to distributing mass quantities of drugs, including heroin, crack cocaine, methamphetamine and marijuana.

During Operation Knockout, federal officials and sheriff's investigators seized more than 100 weapons, and 57 people were charged with crimes.

The investigation began after Ortiz was gunned down by a gang member he was attempting to arrest in connection with a shooting. In 2009, about 170 gang members and associates were taken into custody in the massive, multi-agency operation.

The case also revealed a link between the Hawaiian Gardens gang and the Nazi Low Riders, a prison gang.